so that statistical methods are not necessary for evaluation and errors of the type Shanahan is calculating simply don't matter?
The methods and errors that Shanahan is calculating are impossible. They do not show up in calibrations. In other words, there is no test he can propose to show them, or to falsify his claims. If the problems existed he could propose a method of calibration that would reveal them. It is not possible that the choice of metals would change the arithmetic.